At the turn of 1918-19, and unmentioned in "Mein Kampf," Hitler wore a
red brassard and supported the short-lived Bavarian Soviet Republic,
according to Thomas Weber in the book "Hitler's First War" (Oxford
University Press, 450 pages, $34.95). Perhaps that played a role in
the German National Socialist leader adopting a swastika symbol that
had been used by Soviet socialists on currency with the dates 1917 and
1918.
http://rexcurry.net/ussr-socialist-swastika-cccp-sssr.html
See an image at
http://rexcurry.net/ussr-socialist-swastika1917-1000b.JPG
Although an ancient symbol, the swastika was used sometimes to
represent crossed S-letters for "socialism" under the National
Socialist German Workers Party, as shown by the historian Dr. Rex
Curry, author of "Swastika Secrets."
http://rexcurry.net/book1a1contents-swastika.html
Joseph Goebbels, future Propaganda Minister for Germany's National
Socialism, compared Lenin to Hitler in a favorable light as late as
1925 according to a New York Times article printed in that year.